Control for a double-acting door

ABSTRACT

Apparatus for releasably positioning a double-acting door in a position closing the associated door opening. The apparatus includes a movable positioning bolt which moves into a complementary receiving well formed in the structure defining the door opening with the door in a position closing the opening. Operatively associated with this bolt are two door-opening push bars which are disposed on opposite sides of the door, which bars, with the door in a closing position, and when pushed with a door-opening force, effect withdrawal of the bolt from the well, followed by opening of the door.

United States Patent [19 Miller Apr. 23, 1974 CONTROL FOR A DOUBLE-ACTING DOOR [76] Inventor: Carl J. Miller, 10905 NE. 45th St.,

1 Vancouver, Wash. 98662 22 Filed: Oct. 2, 1972 [21 Appl. No.: 293,847

' 52 us. Cl 49/394, 49/141, 292/92,

. 292/138 [51] Int. Cl E05b 65/06 [58] Field of Search 49/141, 326, 394; 292/33, 292/138, 92

[56] References Cited UNITED STATES PATENTS 1,800,165 4/1931 Waldron 292/92 X 2,216,609 10/1940 B ingham 49/394 X 3,087,323 4/1963 Foster 292/92 X Primary Examiner-J. Karl Bell Attorney, Agent, or F irm-Kolisch, Hartwell &

Dickinson 9 s7 ABSTRACT Apparatus for releasably positioning a double-acting door in a position closing the associated door opening. The apparatus includes a movable positioning bolt which moves into a complementary receiving well formed in the structure defining the door opening with the door in a position closing the opening. Operatively associated with this belt are two door-opening push bars which are disposed on opposite sides of the door, which bars, with the door in a closing position, and when pushed with a door-opening force, effect withdrawal of the bolt from the wel1, followed by opening of the door. 1 l

11 Claims, 6 Drawing Figures 1 CONTROL FOR A DOUBLE-ACTING DOOR SUMMARY AND BACKGROUND OF THE INVENTION opening. The usual Jackson-type closure device includes hydraulic damping mechanism which decelerates movement of the door as such is returned to its closing position.

' One problem with such a door is that it is often swung (and sometimes held) open by wind outside a building, or by excessive air pressure inside the building. This can occur because there is normally no means provided for positively retaining the door in a closing position (until such time asit is purposely swung by a person entering orleaving the building). Such a situation is usually undesirable, since it results in unnecessary heat or air-conditioning loss from a building, and often produces discomfort for those in the buildings lobby.

A general object of the present invention, therefore, is to provide novel door-positioning mechanism for use with a double-acting door which takes care of the problem just outlined in a practical satisfactory manner.

More specifically, an object of the invention is to provide such mechanism which, when used in combination with such a door, releasably yet positively retains'the door in a position closing the associated door opening, without in any way hindering normal use of the door.

Another object of the invention is to provide positioning mechanism of the type generallyoutlined which may be used in combination with a Jackson-type closure device, whereby a double-acting door, after being swung open by someone entering or leaving a building, is automatically returned to and then releasably retained in a position closing its associated door opening.

Still another object of the invention is to provide such a mechanism which can readily be incorporated in various existing double-acting doors with minimal modifications required in the latter. Thus, and according to a preferred embodiment of the invention, the proposed mechanism includes a novel movable positioning bolt which, on a door returning to its closing position, moves into a-comple- .mentary receiving well formed in the structure defining the opening for the door. Operatively associated with this bolt are two door-opening push bars which are disposed on opposite sides of the door, which bars, with the door in a closing position, and when pushed with a door-opening force, effect withdrawal of the bolt from the well, followed bynormal opening of the door. A Jackson-type closure device is operatively connected to the door for biasingit to its closing position, and for decelerating movement of the door as the same returns to such a position.

DESCRIPTION OF THE DRAWINGS These and other objects and advantages attained by description which follows is read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a simplified front elevation illustrating a portion of a building incorporating a double-acting door installation equipped with positioning mechanism as contemplated herein;

FIG. 2 is enlarged fragmentary bottom crosssectional view, taken generally along the line 2-2 in FIG. 1, illustrating details of the proposed positioning mechanism;

FIG. 3 is a cross-sectional view taken generally along the line at 33 in FIG. 2; 1

FIGS. 4 and 5 are views taken generally along the lines 44 and 5-5, respectively, in FIG. 3; and

FIG. 6 is a view similar to the right side of FIG. 2, but illustrating certain parts of the proposed positioning mechanism in different positions from those shown therefor in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION Turning now to the drawings, and referring first to FIG. 1, indicated generally at 10 is a street-level portion of an office building (viewed from the outside) including structure12 defining a generally rectangular door opening 14 in which is disposed a double-acting door 16. Structure 12 includes a' pair of spaced-apart parallel uprights 18, 20 joined adjacent their top ends by a cross member 22. Upright 20 includes a vertical plate 20a whose left face in FIG. 1 defines the right side of door opening 14 in the figure. Plate 20a occupies-a plane substantially normal to the plane of FIG. 1. The particular role played by this plate herein will be de scribed later. The left side margin of door 16 in FIG. 1 is mounted on upright 18 through vertical hinges 24 which allow the door to swing inwardly and outwardly .of the building (i.e., into and out of the plane of FIG.

1, respectively). Indicated in dashed outline generally at 26 is a closure device which biases the door to a closing position. Device 26 is suitably mounted above door 16 adjacent cross member 22, and is operatively connected to the door through conventional linkage mechanism shown also in dashed outline generally. at 28. In FIG. 1, door l6 is shown in a position closing door opening 14. When the door is swung, either inwardly or outwardly, away from this position, and released, closure device 26 through linkage mechanism 28returns the door, with movement of the door decelerated by hydraulic damping mechanism included in the closure device on the door approaching its closing position. The so-called Jackson closure device is typical of one of a number of commercially available units which operate in the manner described.

Door 16 includes a frame comprising a pair of spaced-apart, vertical, tubular stiles 30, 32 joined by upper and lower tubular rails 34, 36 respectively. The cross-sectional configurations of these stiles and rails are substantially the same, and are as illustrated for stile 32 in FIG. 2. These stiles and rails, which define the side and top and bottom margins of the door, support acentral plate glass panel 38. 1

Considering FIGS.2-5 along with FIG. 1, incorporated with door 16 and structure 12 is positioning mechanism, indicated generally at 40, constructed according to the present invention. Generally speaking, positioning mechanism 40 comprises a bolt mechanism 42, and a pair of push bars, or door actuators, 44, 46.

The bolt mechanism includes what might be thought of as a mounting unit 48 which includes an upright front panel 48a, a pair of spaced-apart upright side panels 48b, 48c which are joined to and extend rearwardly of the front panel, and upper and lower generally horizontal panels 48:1, 482, respectively, joined to the side and front panels, and also extending rearwardly of the latter. As can be seen in FIGS. 3 and 5, front panel 48a extends above panel 48d and below panel 48s. Front panel 480 is provided with a central rectangular opening 50 (see FIGS. 3 and 4); side panels 48b, 480 are provided with vertically offset rectangular openings 52, 54, respectively (see FIGS. 4 and 5); and the rear edges of panels 48d, 48 e are provided with vertically aligned slots 56. Opening 52 is below opening 54.

Unit 48 is mounted on and within stile 32 about midway between the ends of this stile. More particularly, front panel 48a is freely received within a matching accommodating opening 58 formed, in the outer wall of stile 32, with the balance of the unit disposed inside the stile. Unit 48 is secured to the stile by means of screw and spring assemblies 60 (see FIGS. 3 and 5). Each assembly 60 includes a screw 60a which connects panel 48a with the inner wall of the stile, and a relatively stiff compression spring 60b that surrounds the shank of the screw, and acts between this panel and wall. Screws 60a'prevent retraction of unit 48 from the stile, and springs 60b hold'the unit in a position with the outside face of panel 48a substantially flush with the outside face of the outer wall of the stile. A filler piece 69 (see FIG. 6) fits snugly between the rear of unit 48 and the inside of stile 32. This filler piece provides additional support for unit 48 in the stile. Piece 69 has been omitted from all but FIG. 6 to simplify the other drawings.

movable member 62, referred to herein as a guided member. Considering particularly FIGS. 3 and 4, member 62 includes a pair of vertically displaced, oppositely inclined, vertical cam surfaces, or camming means, 62a, 62b. As can be seen clearly in FIG. 4, these cam surfaces occupy planes disposed at substantially a right angle to one another. Surface 62a, which is below surface 62b, is at substantially the same elevation as opening 52 in panel 48b. Cam surface 62b is at substantially the same elevation as opening 54 in panel 48c.

Member 62 can slide back and forth (toward and away from panel 480) within panels 48b, 48c, 48d, 48e. The latter panels are thus referred to herein as a guiding support for member 62. Tension springs, or biasing means, 64 (see FIG. 3) bias member 62 toward panel 48a. Springs 64 act between lugs 66 which are secured to the inside face of panel 480, and pins 68 which extend through slots 56 and are secured to the top and bottom sides of member 62. In FIGS. 2, 3 and 4, member 62 is shown in a position engaging panel 48a.

Member 62 herein acts as a means for moving a bolt which is included in mechanism 42, such bolt being in dicated at 70. Bolt 70 extends freely through opening 50 in panel 48a, and is suitably joined to that side of member 62 which faces panel 48a.

Mounted on the underside of panel 48e is a keeper mechanism as contemplated herein, such being indicated generally at 72. Mechanism 72 includes a generally V-shaped keeper element 74 having divergent legs 74a, 74b, this element being pivoted for rocking about a vertical axis on a screw 76 which is secured to the bottom side of panel 48e. A tension spring 78 acts between the outer end of leg 74b and a lug 80 which is joined to the inside face of panel 48a.

Also included in the keeper mechanism is a detent, or keeper release, 82 (see FIG. 6). Detent 82 includes a head 82a, which is slidably received in an accommodating opening 84 provided in the bottom end portion of panel 48a. Head 82a joins with elongated shank 82b that extends slidably through a suitable bore in. a mounting 86 which is secured to the underside of panel 48e. A pin 88 mounted adjacent the left end of shank 82b in FIG. 2 prevents retraction of the detent from mounting 86. Surrounding shank 82b and acting between head 82a and mounting 86 is a compression spring 90.

In FIGS. 2, 3 and 4, bolt 70 is shown in an extended position, wherein it extends a considerable distance outwardly from panel 48a, and hence outwardly from theright edge of door 16 in the figures. Further, bolt 70 extends across the gap between this edge of the door and plate 20a, and into a cutout, or well, 92 which is formed at the proper elevation in the plate. As can be seen in FIG. 4, cutout 92 is substantially centered between the opposite side edges of plate 20a. The significance of this situation will be more fully explained shortly. v

Considering the positions'of detent 82 and keeper element 74, these are best illustrated in FIGS. 2 and 3. Detent 82 is positioned with the outer end of head 82a engaging a button, or projection, 94 which is suitably removably mounted as contemplated herein on plate 20a beneath cutout 92. The left end of shank 82b engages leg 74b in element 74, holding the element in the angular position shown for it in FIG. 2.

Returning now to push bars 44, 46, these are elongated generally L-shaped members disposed on opposite sides of door 16, each extending generally across the width of the door. Bar 44 is disposed on the outside of the door, and bar 46 on the inside thereof. The left ends of bars 44, 46, as seen in FIG. 2, are pivoted on vertical pins 96, 98, respectively, which are mounted on lugs 100, 102, respectively. These lugs are disposed against the opposite side walls of stile 30, and are held thereagainst by means of an elongated screw fastener 104 which extends between the lugs, and freely through suitable accommodating bores formed in the opposite side walls of the stile.

Considering FIGS. 2-5, the right ends of bars 44, 46 in these figures are inturned toward stile 32. The inturned ends of bars 44, 46 extend through mountings 106, 108, respectively, which are suitably secured to the opposite side walls of stile 32. Referring particularly to FIG. 5, it will be seen that upper and lower vertically projecting pins are mounted on these inturned ends which pins are disposed within wells 112, 114 formed within mountings 106, 108, respectively. Pins 110 prevent withdrawal of the push bars ends from the mountings. Compression springs 116 act within these wells between the side walls of stile 32 and pins 110, thus biasing the push bars outwardly with respect to stile 32.

As can be seen clearly in FIG. 5, formed on the inturned ends of bars 44, 46 are vertically offset projections 44a, 46a, respectively. Projection 44a is beneath projection 46a, and extends freely through an opening 118 provided in the right side wall of stile 32 in FIG. 5.

Projection 44a also extends freely through previously mentioned opening 52 in panel 48b. Similarly, projection 46a extends freely through an opening 120 provided in the left side wall of stile 32 in FIG. 5, and also freely through previously mentioned opening '54 in panel 480. Referring for a moment to FIG. 4, projection 44a terminates in a vertical cam surface, or camming means, 122 which substantially parallels and confronts cam surface 62a. Similarly, projection 46a terminates in a vertical cam surface, or camming means, 124 which substantially parallels and confronts cam surface 62b. With bars 44, 46 in the positions shown in FIGS. 2, 4 and 5, cam surfaces 62a, 62b, 122, 124 are not engaged.

Considering now how the apparatus described herein operates, with the various parts in the respective positions shown in FIGS. 1-5, door 16 is releasably retained, as contemplated herein, in a position closing door opening 14. This is because bolt 70 is received within cutout 92 in plate a. As a consequence, neither wind outside building 10, nor excessive air pressure inside the building, can cause the door to swing away from this position.

When someone approaches, for example, to enter the building, he pushes with a slight force, called herein a door-opening force, on bar 44, rocking this bar slightly toward the outside of door 16. Such movement of bar 44 causes cam surface 122 thereon to engage cam surface 62a in member 62. On such engagement, and with continued movement of bar 44 toward the door, member 62 is cammed inwardly (i.e., to the left in FIGS. 2, 3 and 4). It should be noted that such action has no'effect on bar 46. With such camming of member 62, bolt 70 is withdrawn from cutout 92, andis shifted toward a retracted position such as that shown for it in FIG. 6. In addition, as member 62 is thus cammed inwardly, the lower pin 68, which is visible in FIGS. 2 and 6, travels to the left in these figures beyond the left end of keeper element leg 74a.

1 On bolt 70, clearing plate 20a, door 16 is released for inward swinging relative to door opening 14 under the influence of continued pressure on bar'44. And, with inward swinging of the door, the outer end of head 82a in detent 82 moves off button 94, and is then shifted outwardly of panel 48a by spring 90. As a consequence, detent 82 assumes an extended position such as that shown for it in FIG. 6. This movement of the detent permits keeper element 74 to rock counterclockwise in FIG. 2 under the influence of spring 78. More specifically, the keeper element rocks to the position shown for it in FIG. 6, in which position the left end of leg 74a extends across lower slot 56 and blocks lower pin 68 from moving back along this slot. Thus, bolt 70 is held in its retracted position.

When the person (who just opened the door) has entered the building, and released the door, the door is swung back toward its closing position under by closure device 26. The hydraulic damping mechanism therein decelerates movement of the door as it approaches this position. With such return movement of the door, the outer extremity of detent head 82a travels along the arcuate dash double-dot line shown at 126 in FIGS. 2 and 6. It will be noted in FIG. 2 that this line intersects button 94. Because of this, just before the door reaches a fully returned position again closing the door opening, the outer extremity of head 82a brushes against and reengages button 94. With continued return movement of the door, engagement between button 94 and head 82a. causes return movement of detent 82 toward the position shown for it in FIG. 2. Such movement of the detent causes clockwise rocking of the keeper element in FIGS. 2 and 6, which rocking returns the element to the position shown for it in solid outline in FIG. 2. On thekeeper element reaching this position, lower pin 68 is cleared for return movement along lower slot 56. Such return movement, of course, occurs because of the action of biasing springs 64.

Thus, member 62 returns to its original position, with bolt 70 reentering cutout 92. Consequently, door 16 is again positively retained, but releasably so, in its closing position.

It will be obvious that similar action occurs on a person leaving the building, and applying a door-opening force to push bar 46. In this case, cammed retraction of member 62 and bolt 70 results from the engagement of cam surfaces 124, 62b.

Thus, with the positioning mechanism of the invention installed as just described, a double-acting door can be swung open in either direction in essentially a completely normal manner. However, and very importantly, when the door is returned to its closing position,

due to the action of the closure device, the positioning mechanism automatically positively adjusts to retain it in this position. j

If, for any selected interval of time, it is desired to disable the positioning mechanism, this is easily accomplished simply by removing button 94 from plate 20a.

When the door is opened under these circumstances,

and the bolt placed in a retracted position, the bolt will simplyremain in this position. To restore the retaining performance offered by the invention, all one need do is simply reinstall button 94, whereupon it will be brushed against by detent head 82a to release the bolt.

While the invention has been described in connection with a single double-acting door, it should be understood that the mechanism can; also easily be used where double-acting doors are used in side-by-side pairs.

It will thus be apparent that the invention as described readily takes care of the problems mentioned earlier. A double-acting door installation utilizing the invention will act essentially as a conventional installation insofar as opening of the door is-concerned, but additionally, will perform with reasonable retaining of the'door in a closing position. 7 I

It is believed evident from the description herein that the proposed positioning mechanism is one which can easily be incorporated in a variety of types and styles of double-acting doors, with little or no modification required in the latter.

While a preferred embodiment of the invention has been described herein, it is appreciated that variations and modifications may be made without departing from the spirit of the invention.

It is claimed and desired to secure by Letters Patent:

1. In combination with a double-acting door hinged along a side margin for swinging fmovement inwardly and outwardly from a position closing a door opening which is defined by structure bounding the door, mechanism for positioning the door with such closing the door opening comprising a bolt mounted on the door having extended and retracted positions relative to an edge of the door, a bolt well in the structure bounding said door opening positioned to receive said bolt with the latter extended and the door in its closing position, a movable door actuator on each side of the door, each including a camming means, and each being movable with a door opening force applied, thereto,

movable bolt-moving means including camming means interposed between said bolt and both of said actuators, the camming means in said boltmoving means being constructed to coact with the camming means in said actuators, movement of either actuator causing such coaction between its camming means and the camming means in said bolt-moving means, and effecting placement of said bolt in its said retracted position, and

detent means mounted on said door adapted to brush against the structure bounding said door opening with movement of the door inwardly or outwardly and to produce with the bolt in its retracted position and on so brushing the structure movement of the bolt to its extended position.

2. The combination of claim 1, wherein said camming means in said bolt-moving means comprises a pair of oppositely inclined cam surfaces.

3. The combination of claim 1, wherein the door is provided with a closure device biasing the door to its position closing said door opening with the door swung either inwardly or outwardly, and producing decelerated movement of the door as it nears its said closing position, and wherein said detent means starts to brush against the structure bounding said door opening on return movement of the door in either direction toward its closing position under the action of said closure device and before the door fully reaches such position.

4. The combination of claim 1, wherein the door comprises a frame with a tubular stile forming a vertical margin in the door terminating in said edge of the door, and said bolt-moving means comprises a guiding support mounted within said stile, a member mounted for reciprocal movement normal to said edge within said guiding support and joined to said bolt, means biasing said member within said support in a direction extending outwardly of the edge of the door, and which further comprises a keeper for releasably holding said member within said guiding support inwardly on the dooragainst the urging of said biasing means.

5. Incombination with a double-acting door hinged along a side margin for swinging movement inwardly and outwardly from a door opening defined by structure bounding said door,

a push bar on each side of the door movable toward and away from the door, said bars having movable ends adjacent a margin of said door opposite said side margin,

a cam surface associated with each 'push bar which moves in a direction extending toward the opposite side of the door from the side having the push bar when the push bar is pressed toward the door,

a guided member mounted within said opposite side margin of the door guided for reciprocal movement normal to the edge of the door, said member including cam surfaces complementing the cam surfaces associated with said push bars operable to produce movement of the member inwardly from said side edge to a retracted position with movement of either of the push bars toward the side of the door having the push bar,

a keeper adjustable to hold said member in a retracted position,

a keeper release including a detent projecting outwardly from said edge of the door adapted to brush against the structure defining said opening and actuatable to release the keeper from its position holding said member in its retracted position,

biasing means for urging said member toward said side edge on release of the keeper means, and

a bolt joined to said member shiftable to a position extending out from said side edge under the urging of said biasing means.

6. The combination of claim 5, which further comprises a guiding support mounted within said opposite side margin of the door, and wherein said member is mounted for reciprocal movement within said guiding support, said keeper being mounted on said guiding support.

7. Apparatus for releasably retaining in a closing position a hinged, double-acting door which is swingable in opposite directions in a door opening to open and close the same, said apparatus in operative condition comprising i a movable bolt mounted on said door for movement between extended and retracted positions relative to an edge thereof, operable when in its said retracted position to allow free swinging of the door in said opposite directions, and when in its said extended position, and with the door in a closing position, releasably to retain the door in such position,

a pair of independently movable door actuators mounted on opposite sides of the door, each including a camming means, and each being movable with a door-opening force applied thereto to effect opening of the door,

movable bolt-moving means including camming means operatively interposed between said actuators and said bolt, yieldably urging the latter toward its said extended position, the camming means in said bolt-moving means being constructed to coact with the camming means in said actuators, movement of either actuator causing such coaction between its camming means and the camming means in said bolt-moving means, and effecting placement of said bolt in its said retracted position,

a keeper disposed adjacent said bolt operable automatically and releasably to hold the bolt in its said retracted position with movement of the bolt thereto from its saidextended position, .and keeper release including a detent projecting from said edge adapted to brush against the structure defining said door opening, said keeper release being operable with such brushing to release said keeper, thus to release said belt for movement toward its said extended position.

8. The apparatus of claim 7, wherein said camming means in said bolt-moving means comprises a pair of cam surfaces that extend along oppositely inclined planes, and the camming means in said actuators each comprises a cam surface complementing a different cam surface in said bolt-moving means.

9. The apparatus of claim 7, wherein said boltmoving means includes amovable member, and which 9 further comprises a guiding support mounted on the door, which support freely receives said movable member, and wherein said keeper includes a movable element mounted on said guiding support and actibleon said movable member.

10. The apparatus of claim 9, wherein said keeper release is mounted on said guiding support, and is engageable with said movable element.

11. In combination with a double-acting door hinged along a side margin for swinging movement inwardly and outwardly from a position closing a door opening which is defined by structure bounding the door, with such structure including a plate substantially paralleling an edge of the door, mechanism for positioning the door with such closing the door opening comprising a bolt mounted on the door having extended and retractedpositions relative to said edge of the door,

a cutout in said plate defining a bolt well positioned to receive said bolt with the latter extended and the door in its closing position,

a movable door actuator on each side of the door, each being movable with a door-opening force applied thereto,

bolt-moving means interposed between said bolt and both of said actuators, operable to place said bolt in its said retracted position with movement of either of said actuators,

a removable projection mounted on said plate adjacent said cutout, and

detent means mounted on said door adapted to brush against said projection with movement of the door inwardly or outwardly, and to produce with the bolt in its retracted position and on so brushing the projection movement of the bolt to its extended position.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,805,451 7 D d April 23, 1974 lnvent fl Carl J. Miller It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

The inventor" s correct name is --Clair J. Miller--.

Signed and sealed this 10th day of September 1974.

(SEAL) Attest:

- McCOY M. GIBSON, JR. c. MARSHALL DANN Attesting Officer 7 Commissioner of Patents 

1. In combination with a double-acting door hinged along a side margin for swinging movement inwardly and outwardly from a position closing a door opening which is defined by structure bounding the door, mechanism for positioning the door with such closing the door opening comprising a bolt mounted on the door having extended and retracted positions relative to an edge of the door, a bolt well in the structure bounding said door opening positioned to receive said bolt with the latter extended and the door in its closing position, a movable door actuator on each side of the door, each including a camming means, and each being movable with a door opening force applied thereto, movable bolt-moving means including camming means interposed between said bolt and both of said actuators, the camming means in said bolt-moving means being constructed to coact with the camming means in said actuators, movement of either actuator causing such coaction between its camming means and the camming means in said bolt-moving means, and effecting placement of said bolt in its said retracted position, and detent means mounted on said door adapted to brush against the structure bounding said door opening with movement of the door inwardly or outwardly and to produce with the bolt in its retracted position and on so brushing the structure movement of the bolt to its extended position.
 2. The combination of claim 1, wherein said camming means in said bolt-moving means comprises a pair of oppositely inclined cam surfaces.
 3. The combination of claim 1, wherein the door is provided with a closure device biasing the door to its position closing said door opening with the door swung either inwardly or outwardly, and producing decelerated movement of the door as it nears its said closing position, and wherein said detent means starts to brush against the structure bounding said door opening on return movement of the door in either direction toward its closing position under the action of said closure device and before the door fully reaches such position.
 4. The combination of claim 1, wherein the door comprises a frame with a tubular stile forming a vertical margin in the door terminating in said edge of the door, and said bolt-moving means comprises a guiding support mounted within said stile, a member mounted for reciprocal movemeNt normal to said edge within said guiding support and joined to said bolt, means biasing said member within said support in a direction extending outwardly of the edge of the door, and which further comprises a keeper for releasably holding said member within said guiding support inwardly on the door against the urging of said biasing means.
 5. In combination with a double-acting door hinged along a side margin for swinging movement inwardly and outwardly from a door opening defined by structure bounding said door, a push bar on each side of the door movable toward and away from the door, said bars having movable ends adjacent a margin of said door opposite said side margin, a cam surface associated with each push bar which moves in a direction extending toward the opposite side of the door from the side having the push bar when the push bar is pressed toward the door, a guided member mounted within said opposite side margin of the door guided for reciprocal movement normal to the edge of the door, said member including cam surfaces complementing the cam surfaces associated with said push bars operable to produce movement of the member inwardly from said side edge to a retracted position with movement of either of the push bars toward the side of the door having the push bar, a keeper adjustable to hold said member in a retracted position, a keeper release including a detent projecting outwardly from said edge of the door adapted to brush against the structure defining said opening and actuatable to release the keeper from its position holding said member in its retracted position, biasing means for urging said member toward said side edge on release of the keeper means, and a bolt joined to said member shiftable to a position extending out from said side edge under the urging of said biasing means.
 6. The combination of claim 5, which further comprises a guiding support mounted within said opposite side margin of the door, and wherein said member is mounted for reciprocal movement within said guiding support, said keeper being mounted on said guiding support.
 7. Apparatus for releasably retaining in a closing position a hinged, double-acting door which is swingable in opposite directions in a door opening to open and close the same, said apparatus in operative condition comprising a movable bolt mounted on said door for movement between extended and retracted positions relative to an edge thereof, operable when in its said retracted position to allow free swinging of the door in said opposite directions, and when in its said extended position, and with the door in a closing position, releasably to retain the door in such position, a pair of independently movable door actuators mounted on opposite sides of the door, each including a camming means, and each being movable with a door-opening force applied thereto to effect opening of the door, movable bolt-moving means including camming means operatively interposed between said actuators and said bolt, yieldably urging the latter toward its said extended position, the camming means in said bolt-moving means being constructed to coact with the camming means in said actuators, movement of either actuator causing such coaction between its camming means and the camming means in said bolt-moving means, and effecting placement of said bolt in its said retracted position, a keeper disposed adjacent said bolt operable automatically and releasably to hold the bolt in its said retracted position with movement of the bolt thereto from its said extended position, and a keeper release including a detent projecting from said edge adapted to brush against the structure defining said door opening, said keeper release being operable with such brushing to release said keeper, thus to release said bolt for movement toward its said extended position.
 8. The apparatus of claim 7, wherein said camming means in said bolt-moving means comprises a pair of cam surfaces that extend along oppositely inclined planes, and the camming means in said actuators each comprises a cam surface complementing a different cam surface in said bolt-moving means.
 9. The apparatus of claim 7, wherein said bolt-moving means includes a movable member, and which further comprises a guiding support mounted on the door, which support freely receives said movable member, and wherein said keeper includes a movable element mounted on said guiding support and actible on said movable member.
 10. The apparatus of claim 9, wherein said keeper release is mounted on said guiding support, and is engageable with said movable element.
 11. In combination with a double-acting door hinged along a side margin for swinging movement inwardly and outwardly from a position closing a door opening which is defined by structure bounding the door, with such structure including a plate substantially paralleling an edge of the door, mechanism for positioning the door with such closing the door opening comprising a bolt mounted on the door having extended and retracted positions relative to said edge of the door, a cutout in said plate defining a bolt well positioned to receive said bolt with the latter extended and the door in its closing position, a movable door actuator on each side of the door, each being movable with a door-opening force applied thereto, bolt-moving means interposed between said bolt and both of said actuators, operable to place said bolt in its said retracted position with movement of either of said actuators, a removable projection mounted on said plate adjacent said cutout, and detent means mounted on said door adapted to brush against said projection with movement of the door inwardly or outwardly, and to produce with the bolt in its retracted position and on so brushing the projection movement of the bolt to its extended position. 